The present invention relates to the cleaning arts. It finds particular application in conjunction with the cleaning and sterilization of medical instruments and equipment. It will be appreciated, however, that the invention is also applicable to the cleaning of other articles such as food processing equipment, pharmaceutical processing equipment, animal cages, and other equipment.
Various methods and apparatus are known for disinfecting medical instruments and devices. For example, medical instruments and other devices are commonly disinfected using high pressure steam, ethylene oxide gas, low temperature liquid anti-microbial solutions such as peracetic acid or glutaraldehyde, and vapor phase disinfectants such as vapor phase hydrogen peroxide and the like. Each of these disinfection methods has advantages, or is particularly well-suited in certain applications.
Recently, there has been an increased emphasis on the effective cleaning of post-operative debris from medical instruments and devices prior to the disinfection thereof. Likewise, in non-medical device disinfection environments, the effective cleaning of the equipment prior to its disinfection has become increasingly important. When equipment is effectively cleaned prior to disinfection, the organic load encountered by the disinfectant is reduced, thus increasing the effectiveness of the disinfectant. Also, effective cleaning prior to disinfection eliminates the result of a disinfected device or piece of equipment that includes disinfected, but unsightly and potentially dangerous debris thereon. Sterile, dead organisms are known to release toxic pyrogens as they decompose.
Most known disinfection equipment requires that the contaminated medical devices be manually precleaned before the disinfection cycle. Obviously, this labor-intensive approach is time-consuming, expensive, and exposes cleaning personnel to potentially dangerous biological and other contaminants on the equipment being cleaned. Also, the cleanliness of the equipment following the manual cleaning operations cannot be automatically verified, and obviously depends upon the technique of the person who performed the washing or other cleaning.
Therefore, devices that automatically clean and then disinfect medical and other equipment have been developed. Typically, these systems simply carry out a wash cycle for a preset duration. Cleaning is not always certain, especially when the water is not at the ideal temperature, the detergent is not at full strength, water pressure is abnormally low, the cleaning cycle is aborted due to an ineffective timing device, or if other error conditions are present.
For this reason, visual cleaning indicators have been developed that are pre-soiled with a known type and quantity of soil, and then washed with the medical device or other equipment being cleaned. Following the washing cycle and any other associated cycles, such as a disinfection cycle, the cleaning indicator is removed from the wash chamber and visually inspected by a machine operator for any indication that it was not effectively cleaned. The inspection indicates whether the medical device or other equipment was effectively cleaned. Obviously, the visual inspection process is subject to error and operator judgment. It requires a highly trained operator capable of making a subjective determination of cleaning effectiveness.
The present invention contemplates a new and improved cleaning efficacy indicator system and method, and a cleaning device incorporating the same, which automatically assesses cleaning in a real-time, cost-effective, and highly accurate manner.